When running my Vaadin app on Tomcat 8.5 externally from IntelliJ Ultimate 2017.2 on macOS Sierra, I get an error message:
Artifact timepiece-ui:war e
IntelliJ IDEA shows the log files you configure in the Run/Debug configuration settings as the separate tabs in the Run or Debug tool window.
For Tomcat the actual logs are placed under CATALINA_BASE/logs directory. The value of the CATALINA_BASE set by IntelliJ IDEA will be printed in the console of the Run or Debug tool window.
You can also find the log files under idea.system.path/tomcat/.